I'm using Whisker Menu on a convertible and struggle with the problem that it closes automatically if I try to type into the search line using the virtual keyboard. I think, this problem could be solved by introducing an option to make the menu persistent, i.e. stay open even if the focus is lost and close only by clicking the menu button in the panel again.
Graeme Gott referenced this bugreport in commit f311fbec78685cb58f36443f24155e1c61bcf8d3
Add option to stay visible when focus is lost. (bug #12240)
Added in f311fbe.